Indications
Norepinephrine (also called noradrenaline) is a hormone and medicine used in hospital emergencies and intensive care to raise and maintain blood pressure when it is dangerously low, such as in septic shock, other forms of shock, or during cardiac arrest resuscitation and some types of surgery, after enough fluids have been given.
How It Works
Norepinephrine mainly stimulates alpha-adrenergic receptors on blood vessels, causing them to narrow and raising blood pressure. It also has some effect on beta-1 receptors in the heart, which can increase the force of each heartbeat. Together these help keep blood flowing to vital organs such as the brain, heart and kidneys.
Dosage and Administration
Given only by a doctor or nurse in a hospital, usually in an intensive care or emergency setting. It is diluted and given as a continuous infusion into a vein, ideally a large central vein, using an infusion pump. The dose is adjusted minute by minute according to blood pressure and the patient’s response, as prescribed, and is reduced gradually when it is no longer needed.
Interactions
- MAO inhibitors (such as Linezolid) and tricyclic antidepressants (such as Imipramine, Amitriptyline): may cause severe, prolonged high blood pressure.
- Halogenated anaesthetic gases (such as Halothane) and Cyclopropane: risk of serious heart rhythm problems.
- Beta blockers: may cause high blood pressure with a slow heart rate.
- Ergot alkaloids, Oxytocin and other vasopressors: blood pressure may rise excessively.
- Digoxin: higher risk of heart rhythm problems.
Contraindications
- Low blood pressure caused mainly by blood or fluid loss that has not been corrected, except as a temporary emergency measure.
- Blood clots in the blood vessels of the limbs or gut, unless the doctor judges it is needed to save life.
- Use during Cyclopropane or Halothane anaesthesia (risk of arrhythmia).
- Known allergy to the medicine or sulfites in some products.
Side Effects
Possible effects include headache, anxiety, slow or irregular heartbeat, high blood pressure, chest pain, breathing difficulty, reduced blood flow to fingers, toes, gut or kidneys, and reduced urine. If the infusion leaks out of the vein, it can cause severe damage and death of the surrounding tissue.
The medical team monitors continuously. Tell the nurse or doctor at once about pain, burning, coldness or paleness at the drip site or in the fingers or toes, chest pain, a pounding headache, or breathing difficulty.
Pregnancy and Lactation
It may reduce blood flow to the womb and affect the baby, so it is used in pregnancy only when the mother’s life depends on it. It is not known whether it passes into breast milk; the doctor will advise on breastfeeding after treatment.
Precautions and Warnings
Blood volume should be corrected with fluids before or during treatment. Blood pressure, heart rhythm, urine output and the infusion site are monitored closely. If leakage occurs, the infusion is stopped and an antidote such as Phentolamine may be injected into the area. It is not stopped suddenly, to avoid a sharp fall in blood pressure.
Overdose
Overdose can cause very high blood pressure, severe headache, light sensitivity, vomiting, chest pain, irregular heartbeat and bleeding in the brain. The infusion is reduced or stopped and supportive treatment given in hospital.
Therapeutic Class
Vasopressor, sympathomimetic (catecholamine).
Storage
Store as directed on the pack, below 25°C, protected from light; do not use if the solution is brown or contains particles. Hospital use only.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.